As TiddlyWeb has developed, it has become increasingly difficult to give a concise description of what TiddlyWeb is and does and can do for you. It is far easier to list what it has rather than what it does. Part of the reason for this is that TiddlyWeb is lego, a toolkit for getting stuff done. When you buy a screwdriver it doesn't say anything about what you're going to connect, just that you can. So here, in vaguely chronological order of development, is a list of TiddlyWeb features:

See plugins for examples of ways in which the pluggable/extensible things have been plugged and extended.